The present invention relates to an apparatus for conveying articles such as packages or containers filled with material, particularly packages filled with foodstuffs or other consumer products.
In U.S. Pat. No. 3,793,939 of Wieser et al. an installation for sterilization of such articles is described, in which packages are conveyed along a channel through a sterilization zone solely by means of a through-flowing fluid medium in the channel.
Depending upon the packing to be sterilized, a hydraulic pressure is required in the sterilization area which counters the inner pressure within the packing in order to prevent the packing from being destroyed. This over-pressure required by the liquid must be reduced within the cooling zone in the course of cooling until virtual ambient pressure exists at the outlet of the conveyance channel. The pressures brought to bear upon the packing are brought about on the one hand by the hydrodynamic pressure defined by the conveyance speed of the liquid flow; on the other by the hydrostatic pressure of the liquid column in the arrangement. In order to be able to build up and reduce the relatively high pressures in the sterilization and cooling range, it is necessary to arrange the conveyance channels within the cooling zone in a relatively high tower so that, when conveying the packing, the appropriate pressure reduction is achieved from bottom to top. Such high towers, however, have different disadvantages. On the one hand, such towers require very stable supporting structures, which render the arrangement costly and unpractical. On the other, such towers require a significant expense of insulation when freezing of the liquid column should be countered in the cold season; in particular, when the installation is to be shut down outside working hours. Finally, such arrangements do not allow for control of the pressure curve in the conveyance channel since it is determined almost exclusively by the hydrostatic liquid column.